Hydraulically-powered edge trimmer assembly

ABSTRACT

A trimmer assembly for a lawn mower is detachably mountable on a deck of the lawn mower by a housing or shroud that can be secured to the front edge of the deck A mounting frame is pivotally attached to the housing. The mounting frame carries a trimmer head with a plurality of cutting elements secured thereto. The mounting frame and the trimmer head pivotally move between an operational and a non-operational position by a swivel arm secured to the mounting frame. The trimmer head is powered by a hydraulic motor, which operates independently from the operation of the lawn mower.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of my co-pending application Ser. No. 10/713,925 filed on Nov. 14, 2003, entitled “Edge Trimmer Assembly Mountable on a Lawn Mower,” the full disclosure of which is incorporated by reference herein.

FIELD OF THE INVENTION

The present invention generally relates to trimmer devices, and more particularly to an edge trimmer device adapted for attachment to a power lawn mower.

BACKGROUND OF THE INVENTION

Lawnmowers are extensively used by homeowners and commercial services alike. Conventional lawnmowers are generally provided of a walk-behind type and a riding type. When cutting grass it becomes often desirable to cut the edges of the lawn along the sidewalks, around the trees, shrubs and other structures. This task is usually performed using an edge trimmer that allows the user to get closer to the structures, around which the grass needs to be cut.

The conventional trimmers are usually of a string type and can be powered by a gasoline engine or by AC electric power. The edge trimmer is a device sold separately and used separately from a lawn mower. A collection of lawnmowers, edge trimmers, leaf blowers and other such yard devices, takes up valuable storage space in a garage or in equipment shed of a homeowner.

Various attempts have been made to combine the lawnmower with an edge trimmer to reduce the number of steps the user performs when trimming vegetation. However, most of these attempts result in expensive, cumbersome machines that take up considerable space in a tool shed or equipment storehouse of a homeowner.

The present invention contemplates elimination of the drawbacks associated with conventional devices for cutting grass and provision of a grass trimmer that is adapted for mounting on a lawnmower, for instance a riding lawnmower to facilitate and expedite the task of cutting grass with the assistance of a hydraulic motor.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide a retractable edge trimmer that can be mounted on a lawnmower without substantial retrofitting of the lawnmower itself.

It is another object of the present invention to provide a trimmer attachment adapted for retrofitting existing power lawnmower of conventional design.

It is a further object of the present invention to provide a trimmer attachment for a lawnmower that allows directing of vegetation cuttings towards the lawnmower for fine mulching by the lawnmower before discharge.

It is a further object of the present invention to provide a hydraulically-powered lawn-mower/edge trimmer assembly that can be incorporated with a convention lawn mowers.

These and other objects of the present invention are achieved through a provision of a trimmer assembly, which is adapted for detachable mounting on a deck of an existing lawn mover. The trimmer assembly has a shroud, or housing, which is secured to a front edge of the mower deck. A mounting frame is secured to the housing for a pivotal movement between an operational position and a non-operational position. A hinge unit is attached between the mounting frame and the shroud facilitating pivotal movement of the mounting frame to an operational position upon demand.

A swivel arm is attached to the mounting frame. A proximate end of the swivel arm is secured to a handle, which is attached in a pivotal relation to the housing. A stop plate limits the pivotal movement of the handle and, in turn, of the swivel arm, allowing to retain the mounting frame in an operation or a non-operational position. The user moves the handle, which extends above the mower deck to a selected position moving the trimmer assembly into an operational or an idle position.

The trimmer assembly further comprises a trimmer head mounted below the mounting frame and secured thereto. The trimmer head carries a plurality of cutting members for cutting vegetation in the desired area. The trimmer head is powered by a hydraulic motor, which operates independently from a power source of the lawn mower.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the drawings, wherein like parts are designated by like numerals, and wherein

FIG. 1 is a plan view of the trimmer assembly of the present invention mounted on an existing lawnmower deck, with the cutting head in an engaged position.

FIG. 2 is a plan view of the trimmer assembly of the present invention mounted on an existing lawnmower deck, with the cutting head in a disengaged position.

FIG. 3 is a front elevational view of the trimmer assembly in accordance with the present invention powered by a hydraulic motor drive.

FIG. 4 is a cross-sectional detail view showing a mounting frame swivel arm engaging the handle.

FIG. 5 is a schematic view showing a hydraulic motor cooperating with the drive pulley of the cutter head.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to the drawings in more detail, the trimmer assembly of the present invention is generally designated by numeral 10. The trimmer assembly 10 is adapted for mounting to a deck 12 of a conventional lawnmower. A conventional lawn mover has a power means (not shown) that rotates a plurality of driving shafts 14 a, 14 b, and 14 c for rotating grass Cutting blades (not shown) rotating below the deck 12. The driving shafts carry an endless belt 18 of the lawn mover that transmits force between the power driven shafts and the cutting blades.

A frame mounting housing or shroud 24 is secured to a front edge of the deck 12. The shroud 24 has an outer edge 26 that generally conforms to the underlying configuration of the deck 12. The shroud 24 is detachably secured to the deck 12 by bolts or other securing means. A double V-belt pulley shield 28 protects the moving belt 18. The shield 28 is a U-shaped body having free arms 30, 32 secured to the shroud 24 at 34, 36 respectively.

A mounting frame 40 is pivotally secured to the shroud 24 by a hinge unit 42, which allows a limited lateral movement of the mounting frame 40 in relation to the deck 12 and the shroud 24. The mounting frame 40 moves between a belt-engaging position shown in FIG. 1 and a belt disengaging position shown in FIG. 2, as will be explained in more detail hereinafter.

Secured to a free end of the mounting frame 40 is a trimmer head 50. The trimmer head 50 is operationally connected to a hydraulic cutter head motor 52. A high-pressure oil supply line 54 supplies the power fluid to the cutter head motor 50. A return oil hydraulic low-pressure line 56 return the power fluid a hydraulic fluid reservoir 57, schematically shown in FIGS. 3 and 5. A high-pressure hydraulic pump 58 is mounted for operation between the reservoir 57 and a trimmer assembly drive pulley 90, which is connected, through the supply line 54, to the motor 52. The trimmer assembly drive pulley 90 is mounted for operation between the motor 52 and the trimmer head 50. A control valve 92 is mounted in the supply line 54, and a second control valve 94 is mounted in the return line 56.

The trimmer head 50 carries a plurality of cutting elements 62 for cutting vegetation. The cutting members 62 can be special flexible strings conventionally used with edge trimmer assemblies. The cutting members 62 are equidistantly disposed about the circumference of the trimmer head 50. The hinge assembly 42 secures the proximate end of the shroud 96 to a mounting housing or shroud 40, which is adapted for detachable engagement with the deck 12 of an existing lawn mower. A supporting bracket 43 supports the mounting frame 96 on the underside.

A swivel arm 66 is attached above the shroud 24 (FIG. 4) and supports a handle 70, which moves the mounting frame 40 between an engaged and a disengaged position. The handle 70 comprises a gripping portion 72, which extends at an angle above the mounting frame 40 and a vertical portion 74, the lowermost part 75 of which bends at a right angle in relation to the vertical portion 74. The lowermost part 75 of the handle 70 has an opening, through which the swivel arm 66 extends. A retaining nut 77 prevents disengagement of the swivel arm 66 from the handle portion 75.

A compression spring 76 is mounted about the lowermost part of the portion 74 above the lowermost part 75. The spring 76 urges against the part 75 at its lower end and against a bottom lever bracket 78—at its upper end. A U-shaped bracket 82 (FIG. 4) extends below the bottom lever bracket 78. The U-shaped bracket 82, at its lower part, supports a stop plate 80. The upper part of the U-shaped bracket 82 is detachably secured, such as by bolts 85, to the bottom lever bracket 78. An upper bracket 84 has a lower portion, which is secured to the lower lever bracket 78 and the U-shaped bracket 82 by the bolts 85. The portion 74 of the handle 70 extends through corresponding aligned openings formed in the brackets 78, 82 and 84.

The portion 75 rests on the stop plate 80, which delimits the movement of the handle 70 in relation to the shroud 24. When the user moves the handle 70 into an engaged position, the stop plate 80 limits the mounting frame 40 from moving beyond the limits of the hinge. The compression spring 76 allows retaining of the handle 70 and the swivel arm 66 in the selected position. When the user moves the handle 70 pushing the swivel arm 66 and the mounting frame 40 into a disengaged position, the stop plate 80 and the spring 76 arrest movement of the handle, allowing the mounting frame to retain in a disengaged position.

When a user wishes to activate rotation of the trimmer assembly 10, the user moves the handle 70 into a position shown in FIG. 1. By activating the motor 52, the user causes the rotational force to be transmitted to the trimmer head 50. Rotation of the trimmer head 50 causes the cutting members 62 to rotate and cut vegetation on contact. After the user finishes trimming of the desired vegetation, the trimmer assembly 10 may be disengaged. In this position, which is illustrated in FIG. 2, the user moves the handle 70, pushing the swivel arm 66 and forcing the mounting frame 40 to pivot about the pivot assembly 42. In this disengaged position, the cutting members 62 are not operational.

The trimmer assembly of the present invention is mounted forward of the cutting blades carried by the existing lawn mower. As a result, the cuttings generated by the cutting elements of the trimmer head are moved by air current to the back of the trimmer assembly, in the path of the lawn mower cutting blades. If the lawn mower blades are rotating, the cuttings are then further chopped into smaller pieces and may be discharged through a side of the lawn mower similar to the cuttings generated by the lawn mover per se.

The trimmer assembly of the present invention is easily positioned and easily detached from a conventional lawn mower. The conventional law mowers may be inexpensively and relatively easy retrofitted with the trimmer assembly of the present invention. Since the trimmer assembly is mountable on the existing structure it does not require as much space for storage as conventional edge trimmers.

The present invention provides for a hydraulic motor as a drive option for operating the edge trimmer assembly independently of the lawn mower. The ease of rotating the cutter head facilitates the grounds maintenance operation and allows the user to cut thicker vegetation, if necessary without necessarily engaging the lawn mower. It is envisioned that other power drive options, such as for instance a re-chargeable battery, will become apparent to those skilled in the art. It is envisioned that the pivotal movement of the trimmer attachment may be performed by moving the hinge along a vertical rotational axis, while moving the swivel arm along a horizontal rotating axis, if desired.

Many other changes and modifications may be made in the design of the present invention without departing from the spirit thereof. I, therefore, pray that my rights to the present invention be limited only by the scope of the appended claims. 

1. A trimmer assembly mountable on a lawn mower having a mower deck and a front edge, the trimmer assembly comprising: a trimmer head; a mounting frame supporting the trimmer head forward of the front edge of the lawn mower; a means for pivotally connecting the mounting frame to the front edge to facilitate movement of the trimmer head between an operational position and a non-operational position in relation to the mower deck; and a means carried by the mounting frame for transmitting rotational force to the trimmer head, said means comprising a power source operationally connected to the trimmer head for imparting rotation on the trimmer head independently from operation of the lawn mower.
 2. The trimmer assembly of claim 1, further comprising a housing adapted for detachable mounting on the front edge of the mower and pivotally connected to said mounting frame.
 3. The trimmer assembly of claim 2, wherein said means for pivotally connecting the mounting frame comprises a hinge unit mounted between the housing and the mounting frame, a swivel arm extending between the mounting frame and the housing and a handle operationally connected to the swivel arm for pivotally moving the mounting frame in relation to the mower deck upon demand.
 4. The trimmer assembly of claim 3, wherein said means for pivotally moving the mounting frame further comprises a means for limiting rotational movement of the handle.
 5. The trimmer assembly of claim 4, wherein said means for limiting rotational movement of the handle comprises a stop plate mounted below a handle and a compression spring engaging a lower portion of the handle, said compression spring urging, at its upper end, against a lever bracket mounted above the housing.
 6. The trimmer assembly of claim 1, wherein said means for transmitting rotational force to the trimmer head comprises a hydraulic motor mounted above the trimmer head, a pump for supplying a power fluid to the hydraulic motor, and means for regulating supply of the power fluid to the motor.
 7. The trimmer assembly of claim 6, wherein said means for regulating supply of the power fluid to the motor comprising a first control valve mounted in a fluid supply line and a second control valve mounted in a fluid return line.
 8. The trimmer assembly of claim 7, wherein said return line is fluidly connected to a source of the power fluid.
 9. The trimmer assembly of claim 1, wherein said means for transmitting rotational force to the trimmer head comprises an hydraulic motor mounted on the mounting frame and operationally connected to the trimmer head.
 10. A trimmer assembly mountable on a lawn mower having a mower deck and a front edge, the trimmer assembly comprising: a trimmer head; a mounting frame supporting the trimmer head forward of the front edge of the lawn mower; a housing adapted for detachable engagement with the front edge of the mower deck; a means for pivotally connecting the mounting frame to the housing to facilitate movement of the trimmer head between an operational position and a non-operational position in relation to the mower deck, said means comprising a hinge unit mounted between the housing and the mounting frame, a swivel arm extending between the mounting frame and the housing, and a handle secured to the housing and operationally connected to the swivel arm for pivotally moving the mounting frame in relation to the mower deck upon demand; and a means carried by the mounting frame for transmitting rotational force to the trimmer head independently from operation of the lawn mower, said force transmitting means comprising an hydraulic motor mounted on the mounting frame and operationally connected to the trimmer head.
 11. The trimmer assembly of claim 10, wherein said hydraulic motor is operationally connected to a source of a power fluid and a pump operationally mounted between the source of the power fluid and the hydraulic motor.
 12. The trimmer assembly of claim 11, further comprising a means for regulating supply of the power fluid to the motor, said regulating means comprising a first control valve mounted in a supply line extending between the pump to the motor and a second control valve mounted in a return line extending between the motor and the source of the power fluid.
 13. The trimmer assembly of claim 10, further comprising a means for limiting rotational movement of the handle, said means comprising a stop plate mounted below a handle and a compression spring engaging a lower portion of the handle, said compression spring urging, at its upper end, against a lever bracket mounted above the housing.
 14. A trimmer assembly mountable on a lawn mower having a mower deck and a front edge, the trimmer assembly comprising: a trimmer head; a mounting frame supporting the trimmer head forward of the front edge of the lawn mower; a means for pivotally connecting the mounting frame to the front edge to facilitate movement of the trimmer head between an operational position and a non-operational position in relation to the mower deck; and a means carried by the mounting frame for transmitting rotational force to the trimmer lead, said force transmitting means comprising a hydraulic motor mounted on said frame above the trimmer head and operationally connected to the trimmer head for transmitting rotation force to the trimmer head independently from the law mower, said hydraulic motor being operationally connected to a supply of a power fluid through a pair of fluid regulating control valves.
 15. The trimmer assembly of claim 14, wherein said means for pivotally connecting the mounting frame comprises a hinge unit mounted between the housing and the mounting frame, a swivel arm extending between the mounting frame and the housing, and a handle operationally connected to the swivel arm for pivotally moving the mounting frame in relation to the mower deck upon demand.
 16. The trimmer assembly of claim 14, wherein said means for pivotally moving the mounting frame further comprises a means for limiting rotational movement of the handle, said means for limiting rotational movement of the handle comprises a stop plate mounted below a handle and a compression spring engaging a lower portion of the handle, said compression spring urging, at its upper end, against a lever bracket mounted above the housing.
 17. The trimmer assembly of claim 14, further comprising a pump operationally mounted between the hydraulic motor and the supply of power fluid. 